Waterproof electric heater and its method of manufacture



June 26, 1923.

- L. P. HYNES WATERPROOF ELECTRIC HEATER AND ITS METHOD OF MANUFACTURE Filed Oct. 18, 1921 INVENTOR ofu 0 BY I A TT RNE Y Patented June 26, 1923..

P. HYNES, @F ALBANY, NEW YGRK,

QOMPANY, @F ALBANY, NEW" JOEE,

WATERPROOF ELECTRIQ HEATER Application riled October is.

To all whom it may concern Be it known that 1', LEE l-lYNEs, a citizen of the United States, residing at Albany, in the county of Albany and State of New York, have invented certain new and useful improvements in Waterproof Electric Heaters and Their Methods of Manufacture, the following being a full, clear, and exact dis closure of the one form of my invention which I at present deem preferable.

or a detailed description of the present form of my invention, reference may be had to the following specification and-to the .accompanying drawings forming a part thereof, whereinfig. 1 is a side elevation of my device partly in section and ig. 2 is an end view thereof.

Figures 3 and 4 are sectional views taken on lines 3-3 and ll-4, respectively, Figare l. i

My invention relates to a waterproof electric heater for heating air or gasesas well as l quids, or solids. It comprises an external metallic shell of steel or other suitable metal which is shaped by pressing a tube into a smaller coil-containing tube with outside radiating ribs or flanges produced by the surplus metals, and at each end has a screw thread formed thereon by which the end seals and terminal connectors'may be ape plied. The ribs or flanges will be of a double thickness of sheet metal.

Referring to the drawing 1 represents a steel tube which was originally ofplain cylindrical form, but which for the greater part of its length has been compressed laterally until it has assumed'the form of a smaller central tube of about half the original diameter with two flat flanges projecting radially therefrom and 180 degrees apart. These flanges are shown at 3, 3 and are formed by the surplus metal of the original tube over what is required for the smaller tube. The two ends of the tube are left of the original size and have a screw thread rolled or pressed into them. Inside the central tube isextended a tubular lining 4 of refractory insulating material and inside of this lining is the heating coil 5. The lining should closely fit the inside of the tube although it may be free enough to be pushed into it. The closer it fits the more eiiicient will be the transmission of heat to the tube and the less will be the danger of breakage slipped over this stem 6 and the nsane IBUEESGLZDATED @AR EEATIING Serial lic. 553215455.

culation. each end of the coil is a stem 6 which passes through an bushing is screwed a metallic insert 8 ch is screwed into larger bushing 8 that, in turn, is screwed end of the original tube. Bushing 9 has deep square co ntersinlr at its outer end and shoulder hat overlies the end of said tube. A connecting screw 10 is driven aforesaid insert 8 and serves as the terminal screw for one end of the heating coil. The mode of assembling the described parts is as follows: i issuming that lining l is place in the central tube, the coil with a stemv 6 secured to each end has the bushing 7 slipped over stem U stem then screwed into the insert 8 in bushing :9. The coil can then be threaded into lining and the bushing 9 firmly screwed into e main tube by means of a socket wrench fitting into the square countersink. That will complete the assembling at one end of the heater leaving the opposite end with the opposite stem 6 protruding from the lining. Since the heater coil is flexible its end be drawn out of the lining tube far enough to permit the bushing 7 being stem screwed into the insert 8 by means of small pliers or by a wrench engaging" a flat or hexagonal section on the stem. then remains to insert bushing 9', which may be done by screwthe insert- 8 back into bushing 8 thereby putting a temporary twist in coil 5. This twist will be relieved as the bushing 9 is finally screwed into the main tube, but will be permissible by reason of the flexibility and numerous turns of the heating coil. By a reverse series of steps the coil may be re :moved. and replaced, if desired, by a new coil, this being possible by the fact that the coil is free in any internal engagement with the lining which would obstruct its passage and the passage of the terminal stems 6 which are secured to the coil before its insertion and go with it to make up a separate unitary member.

The construction above described consti tutes a waterproof heater of a substantial rugged character with adequate radiating surfaces. Moreover, additional wings may be formed on the tube by pressure tosecurc any desired area of radiating surface. The shapingof the external metal by pressure avoids the need of joints therein requiring to he mode Wstertight by riveting or sole ering. It is strong and cheep to make.

W-. I claim as new and desire to secure by l ters Potent is:

1. The mode of manufacturing :in electric heater which consists in shaping s metallic shell by 1 ressing .9. tube into the tesired form and inserting therein e heating; conductor with insulation and connecting ter T heat which consists in slisping on external metallic sh ll by pressing tub-e into ribbed form sud riser-ting; therein a heating conductor with insulutions and connecting terininels.

.Lhe mode of manufacturing on electricheater "iel lCll consiss in shun metallic shell pressine" form With screw ends u in" ting ther s heating conduct with insuwwion and con nesting}; terminals.

lhe mode of manufacturing electric heater which consists in shaping en externcl shell into :1 tubular form with doubled is sting; ribs rind inserting conductor with insulation connecting terminals.

5. The mode of manufacturing an electric heater which consists in forming on shell by compressing e tube into a tube or smaller dimensions with outside ribs and inserting in the receptacle thus formed a. heating conductor with insulation and connesting terminals.

*6. -'lhe mode of manufacturing on electric ester which consists in reducing by pressure metallic tube to form internal seating; portions thereon for the heating conductor, and inserting therein on the said seating portions an insulated heating conductor with connecting terminals.

7. The mode of manufacturing an electric heater which consists in shaping by pressure a. sheet motel shell into e. tubular ribbed form, inserting therein en insulating; lining, threading; therethrough within -the lining a heating conductor, and closing the ends of the. shell by insulating bushings through Which the connecting terminals extend.

8. An electric heater comprising a pressed metal shell in the form of e ribbed tube, insulation seated in said tube, a heating conductor within the tube, insulating bushings closing the ends of the tube and connecting terminals for said conductor extended tlirou li said bushings.

9. An electric heater comprising a pressed metal shell in the form of e ribbed tube with screw-threaded ends, an insulated heating conductor Within said shell, screw bushings in the ends of the shell and connecting termirials for the said conductor passing through said bushings.

10. An electric heater comprising a tubuternel ribs formed 0' double layer of metal. 13. i'in. electric he r comprising 21 sheet l tube with external metal shell ribs, i tube, on end block, a stem 5 connecting scic. of seid conductor and e). for said block.

14;. An electric heater comprising, sheet metal shell "wi screw ends, on heating conductor in s shell, seating bushings screwed into the ends the shell enl connecting terminols passing through said bushin 15. electric ecomprising s rnetsllie shell, or refractory lining there-for close;

fitting the shell, and rreely ner conductor in said containing; 2L h ough bushi iernal connector 1 n s neutino' coil sertoble in seid lining with the lining 1r. piece in the shell.

motel- 18. An electric hector comprising 9. lic shell, e refractory lining theretor closel fitting; the shell, end it hosting coil extending through said lining, and free thereof iute nelly.

17. An electric heater comprising at motellic shell, a. refractory lining there-for of tubular form. and e. hosting coil having at terininel attached thereto smaller than the interncl dimension of ssid lining, whereby both coil and terminal may be passed therethrough.

18. An electric heater comprising a. sheet metal shell, 21 tubular lining therefor in close contact therewith. and removable heating coil extending through said lining.

19. An electric heater comprising a metallic'sliell, a tubular refractory lining in close contact therewith, a removable heatin coil extending through said lining. end bus ings, and attachment terminals for the external circuit located in recesses in the said bushings.

20. An electric heater comprising a pressed metal shell having; integral ribs and tubular ends, a refractory tubular lining of less diameter than the ends, a. heating coil extending freely through said lining with end conbushings in said shell,-metallic heating coil in said lining having rigid stems insulating ends, and connecting devices for the respective ends of said coil passing through said bus ings.

23. 11 electric heater comprising a pressed metallic shell having its central part formed as a tube having extending ribs and its ends formed as larger tubes but of less diameter than the said ribs, a refractory lining fitted into the central tube, the larger end tubes, and rigid connecting devices for the respective ends of the heating coil passing through said bushings.

Signed at Albany, county of Albany, State of New York, this 14th day of October, 1921.

LEE P. HYNES.

insulating bushings in' 

